Doublerot.m

Fokker-Planck double angle spinning context. Generates a Liouvillian superoperator and passes it on to the pulse sequence function, which should be supplied as a handle.

Syntax

    answer=doublerot(spin_system,pulse_sequence,parameters,assumptions)

Arguments

    pulse_sequence  - function handle to a pulse sequence, which must have 
                      the following call syntax:
                   
                      answer=pulse_sequence(spin_system,parameters,H,R,K)

                      where parameters is a structure described below, H is
                      the Hamiltonian, R is relaxation superoperator, and K
                      is the kinetics superoperator

    assumptions     - the string that will be passed to assume.m when 
                      the Hamiltonian is built

    parameters.rate_outer - outer rotor spinning rate in Hz

    parameters.rate_inner - inner rotor spinning rate in Hz

    parameters.axis_outer - spinning axis of the outer rotor,
                            given as a normalized 3-element
                            vector

    parameters.axis_inner - spinning axis of the inner rotor,
                            given as a normalized 3-element
                            vector

    parameters.rank_outer - maximum harmonic rank to retain in
                            the solution (increase till conver-
                            gence is achieved, approximately
                            equal to the number of spinning si-
                            debands in the spectrum) for the
                            outer rotor

    parameters.rank_inner - maximum harmonic rank to retain in
                            the solution (increase till conver-
                            gence is achieved, approximately
                            equal to the number of spinning si-
                            debands in the spectrum) for the
                            inner rotor

    parameters.rframes    - rotating frame specification, e.g.
                            {{'13C',2},{'14N,3}} requests second
                            order rotating frame transformation
                            with respect to carbon-13 and third
                            order rotating frame transformation
                            with respect to nitrogen-14

Additional subfields may be required by the pulse sequence. The parameters structure is passed to the pulse sequence with the following additional parameters set:

    parameters.spc_dim  - matrix dimension for the spatial
                          dynamics subspace

    parameters.spn_dim  - matrix dimension for the spin 
                          dynamics subspace

Outputs

This function returns the powder average of whatever it is that the pulse sequence returns.

Examples

See nmr_solids and nmr_overtone directories in the example set.

Notes

1. Arbitrary order rotating frame transformation is supported, including infinite order. See rotframe.m for further information.
2. The state projector assumes a powder - single crystal DOR is not currently supported.
3. The function supports parallel processing via Matlab's Distributed Computing Toolbox - different system orientations are evaluated on different labs.

See also

powder.m, liquid.m, roadmap.m, singlerot.m, crystal.m, imaging.m, gridfree.m, floquet.m

Version 2.2, authors: Ilya Kuprov